For decades, the Childhood Autism Rating Scale, Second Edition (CARS2), has stood as a cornerstone in Cars Autism Diagnostic Tool assessments. Renowned for its empirical validation, CARS2 effectively distinguishes between children with autism and those with intellectual disabilities. Furthermore, it differentiates between varying severities of autism, from mild-to-moderate to severe.
The updated CARS2 broadens its applicability, particularly for individuals on the higher-functioning end of the autism spectrum. This revision caters to those with average or above-average IQs, enhanced verbal abilities, and subtle social and behavioral challenges. While maintaining the original test’s simplicity and clarity, CARS2 introduces new forms and features. These enhancements aid in integrating diagnostic information, evaluating functional skills, providing parent feedback, and formulating targeted intervention strategies.
Exploring the CARS2 Forms
CARS2 offers three distinct forms to accommodate diverse needs:
CARS2-ST (Standard Version Rating Booklet): This form mirrors the original CARS and is designed for children under 6 years old, individuals with communication difficulties, or those with below-average IQs.
CARS2-HF (High-Functioning Version Rating Booklet): This alternative form is tailored for verbally fluent individuals aged 6 and older with IQ scores above 80, addressing the nuances of autism in high-functioning individuals.
CARS2-QPC (Questionnaire for Parents or Caregivers): This unscored questionnaire gathers crucial background information from parents or caregivers, enriching the data used for CARS2-ST and CARS2-HF ratings.
Deep Dive into the Standard and High-Functioning Forms
Both CARS2-ST and CARS2-HF encompass 15 items that evaluate key functional areas relevant to autism diagnosis:
- Relating to People
- CARS2-ST: Imitation; CARS2-HF: Social-Emotional Understanding
- CARS2-ST: Emotional Response; CARS2-HF: Emotional Expression and Regulation of Emotions
- Body Use
- CARS2-ST: Object Use; CARS2-HF: Object Use in Play
- CARS2-ST: Adaptation to Change; CARS2-HF: Adaptation to Change/Restricted Interests
- Visual Response
- Listening Response
- Taste, Smell, and Touch Response and Use
- CARS2-ST: Fear or Nervousness; CARS2-HF: Fear or Anxiety
- Verbal Communication
- Nonverbal Communication
- CARS2-ST: Activity Level; CARS2-HF: Thinking/Cognitive Integration Skills
- Level and Consistency of Intellectual Response
- General Impressions
While the Standard form retains the items from the original CARS, the High-Functioning form’s items are adapted based on contemporary research concerning high-functioning autism and Asperger’s Syndrome.
Clinicians utilize a 4-point scale to rate individuals on each item. Ratings consider not only the frequency of a behavior but also its intensity, peculiarity, and duration. This refined approach offers diagnostic flexibility while still yielding quantifiable results.
The Rating Booklets for both versions provide practical space for clinical notes and documentation. They include brief descriptions of each rated area, serving as rating criteria reminders and a framework for communicating results to parents. Furthermore, they present cutoff values for quick determination of whether further evaluation is needed.
Total Raw Scores are calculated by summing item ratings. Each form includes a graph for easy conversion of Raw Scores to standard scores or percentile ranks, based on a clinical sample of 1,034 individuals with autism spectrum disorders. The CARS2 Manual provides score interpretation guidelines, intervention suggestions, and illustrative case examples.
Leveraging the Parent/Caregiver Questionnaire
The CARS2-QPC, completed by parents or caregivers, provides clinicians with supplementary information to inform CARS2-ST or CARS2-HF ratings. This questionnaire often serves as a basis for follow-up interviews, allowing clinicians to clarify and interpret caregiver responses.
The CARS2-QPC explores areas such as early development, social, emotional, and communication skills, repetitive behaviors, play patterns, routines, and unusual sensory interests.
Why CARS2 is a Leading Autism Diagnostic Tool
CARS2 stands out as an invaluable cars autism diagnostic tool due to its comprehensive features:
- Spectrum Coverage: It addresses the entire autism spectrum as defined by empirical research.
- Extensive History: It is rooted in decades of application with thousands of individuals referred for autism assessment.
- Broad Applicability: It is suitable for virtually all ages and functional levels.
- Objective and Quantifiable: It delivers concise, objective, and quantifiable ratings based on direct behavioral observation.
- Strong Diagnostic Correlation: Scores exhibit a consistent, strong, positive, and specific relationship with an autism diagnosis.
- Reliable and Consistent: Ratings demonstrate reliability across time, settings, information sources, and raters.
With its updated form for higher-functioning individuals, structured caregiver information gathering, and guidelines linking scores to intervention, CARS2 remains a premier cars autism diagnostic tool available today.
